A lathe is a machine tool having one or more movable cutting elements which operate on a workpiece rotated by a headstock. The cutting elements, headstock and other movable components are in turn mounted on a bedway. The bedway on which the cutting elements move is typically manufactured from metal, such as steel or cast iron, and is secured to a base. The base itself is a large, bulky assembly which firmly anchors all of the machine components.
Current machine tools are designed to repeatedly reproduce cuts of high accuracy and extremely small tolerances. Currently, the military, aerospace and other industries are demanding even smaller tolerances of machined parts. Such exceptionally small tolerances require that numerous factors affecting the overall machine tool and the relationship between its individual component parts be controlled. For example, temperature fluctuations generated during machine operation can adversely impact the overall accuracy of the machine tool. In those cases, the dissimilar thermal expansion coefficients between the various metal components of the machine tool act to distort alignment. This is particularly true of the headstock, which contains a spindle rotating at extremely high speeds and consequently generating substantial amounts of heat. Also, heat transferred from the drive motor to the spindle and the bearings cause thermal deformation or expansion of the machine components, resulting in inaccurate alignment and cuts.
From the above, those skilled in the art will understand that there exists a need for an improved system of transferring heat generated at the headstock during machining of a workpiece. The resulting system and machine is one which is provided with means for effectively cooling the headstock and spindle assembly thereby assuring repeated cuts of small and extremely accurate tolerances.